OUR EVIDENCE STANDARDS

Make accurate information interesting — never the reverse.

Parenting content is full of confident nonsense. Our standard is different, and it’s public:

Looking for the sources behind a specific post? Jump straight to the citations.

The rules we publish by

Every factual claim is sourced. Posts, handbooks, emails — each carries its citations, on the slide or on the page.
We verify before we publish. A claim enters our internal evidence database only after the source is confirmed to exist and to actually support the statement as worded — title-only citations don’t count.
Source hierarchy. We prefer, in order: systematic reviews and meta-analyses; strong peer-reviewed studies; professional medical organizations (AAP, ACOG); government health agencies (CDC, NIH); major academic institutions and children’s hospitals.
Nuance survives. A single small study is never presented as settled fact. Correlation is not upgraded to causation. Where the evidence is mixed, we say so.
No invented anything. No fabricated statistics, studies, experts, or quotes — ever. If we can’t verify it, we don’t publish it.
Corrections are public. If we get something wrong, we fix it and say we fixed it. Spot an error: hello@wavelengthparenting.com.

Sources we regularly draw on

American Academy of Pediatrics / HealthyChildren.org · CDC · NIH & NIMH · ACOG · JAMA Pediatrics · Pediatrics · Journal of Adolescent Health · the C.S. Mott Children’s Hospital National Poll · and the peer-reviewed developmental literature. Full citations for individual posts are listed further down this page, and inside each handbook.

Citations, post by post

If you arrived here from one of our posts, this is where its sources live. For every factual claim we publish, you get three things: the full citation, what the source actually found, and — where it matters — what it doesn’t show. We print the limitation next to the finding, because a source that is weaker than it sounds is the most common way parenting content goes wrong.

This list begins with posts published on and after 25 August 2026. Earlier posts are being added as each one is re-checked against our evidence database — we don’t list a post here until that check is done.

Instagram · 26 August 2026

“Why is my 12-year-old so moody?”

The claim, as we published itA meta-analysis of parent–child conflict found the rate of conflict actually declines across adolescence — while the heat of it rises, tracking with pubertal maturation.

Source: Laursen B, Coy KC, Collins WA. “Reconsidering Changes in Parent-Child Conflict across Adolescence: A Meta-Analysis.” Child Development 1998;69(3):817–832.
What the source found: Conflict rate and total conflict declined from early to mid adolescence, and again from mid to late adolescence. Conflict affect — the intensity — increased from early to mid adolescence, and showed a positive linear association with pubertal maturation.
What it doesn’t show: It is a 1998 meta-analysis, and it is dated. We use it because it remains the canonical quantitative anchor for this question, and because its finding is routinely misremembered as “conflict increases.” It reports associations, not causes: it does not show that puberty makes arguments hotter, only that the two track together.

The claim, as we published itPer NIMH, the emotion and reward systems ramp up around puberty while judgment and self-control keep maturing into the mid-to-late twenties.

Source: National Institute of Mental Health. “The Teen Brain: 7 Things to Know.” nimh.nih.gov
What the source found: Verbatim from NIMH: “The brain finishes developing and maturing in the mid-to-late 20s… the prefrontal cortex is one of the last parts to mature.” Heightened emotional intensity and sensation-seeking in this window are described as developmentally normal.
What it doesn’t show: This is a government agency summarising a body of neuroscience literature, not a single study. It describes typical development across a population. It says nothing about any individual child, and it is not a diagnosis or an explanation for a specific hard week.

See the original post →

Instagram · 25 August 2026

“How do you talk to your son about puberty when nothing visible has happened yet?”

The claim, as we published itBoys’ puberty starts with a change no parent can see — and here is the order it actually happens in.

Source: American Academy of Pediatrics. “Physical Development in Boys: What to Expect During Puberty.” HealthyChildren.org. Corroborated by NIH MedlinePlus, “Puberty” (medlineplus.gov), and by Herman-Giddens et al., Pediatrics (2012).
What the source found: Verbatim from the AAP: “A near doubling in the size of the testicles… announces the advent of puberty. Just after the peak of the growth spurt… voice may ‘crack’ as it deepens.” Boys typically begin puberty between ages 9 and 14, and the first change in the sequence is not one anybody can see.
What it doesn’t show: Our confidence is high for the age range and for the order of the sequence, and only moderate for any exact average age — published averages vary by cohort and by how onset was measured. One note on provenance: the Herman-Giddens 2012 figures were read in a secondary summary, not in the journal itself, so we treat them as corroboration rather than as our primary source.

The claim, as we published itThe one change more than half of boys get that almost nobody warns them about.

Source: Metwalley & Farghaly. Annals of Pediatric Endocrinology & Metabolism (2024). DOI 10.6065/apem.2346142.071 · PMID 38712491.
What the source found: Roughly 50–60% of adolescent boys experience temporary breast-tissue enlargement (gynecomastia), peaking around ages 13–14. It resolves on its own in more than 90% of cases within three years.
What it doesn’t show: This is a peer-reviewed review article, and the figures are typical ranges rather than a precise population count. It describes what is common; it is not a substitute for a pediatrician looking at your particular son, and persistent or painful changes are a conversation to have with one.

See the original post →

Think we have got one of these wrong, or want the reasoning behind a claim we haven’t listed yet? Write to hello@wavelengthparenting.com — corrections get published, not buried.

Education, not medicine: our content helps you understand and talk with your child. It never replaces the professionals who know them. Crisis resources: call or text 988, 24/7.